The present invention generally relates to an apparatus for mounting antennas on a locomotive, and more specifically, to a modular antenna array for a locomotive.
FIG. 1 illustrates a locomotive, including a locomotive cab 118. Although FIG. 1 depicts a prior art antenna array 100 mounted to the locomotive cab roof 106, the present invention modular antenna array may be affixed or otherwise mounted to the locomotive cab roof instead.
FIG. 2 illustrates a prior art locomotive having a plurality of antennas 102A-H mounted on the roof 106 of the locomotive cab 118. The antennas 102A-E may comprise different types of antennas, including but not limited to a cellular antenna 102A, a distributed power antenna 102B, a tri-band antenna 102C, a GPS antenna 102D, a head of train antenna, WIFI or WLAN antenna 102E, data radio antenna (e.g., a 220 MHz antenna) 102F, an end of train antenna 102G, voice radio antenna (e.g., VHF voice antenna) 102H, a digital cellular antenna, a GSM-R antenna, electronic train management antenna, or the like. In mounting an antenna to the locomotive cab roof 106, a hole is drilled to accommodate the wiring and/or a portion of the antenna body. The wiring is fed through the hole into the locomotive cab, where it is connected to a device for utilization of that particular antenna. The body of the antenna 102 is affixed to the roof 106 of the locomotive cab 118 by use of fasteners, epoxy, or the like.
However, this prior art system has several shortcomings. For example, each antenna cannot easily be arranged or rearranged in order to overcome communication or RF interference with other antennas. Additionally, because the roof of the locomotive is susceptible to harsh environmental conditions, the prior art system and the locomotive cab is susceptible to water ingress due to deterioration of the joint (e.g., fastener, epoxy, room temperature vulcanizing (RTV), etc.) between the body and antenna, and/or the locomotive roof. The replacement or addition of an antenna in this prior art system also proves to be difficult and labor intensive. Replacement of the antenna first requires the removal of the deteriorated joint and all of the wiring extending from the previous antenna to the device associated therewith, which is typically located in the locomotive cab. Then, new wiring is fed into the locomotive cab, where it is connected to a device for utilization of that particular antenna. The body of the antenna is ultimately affixed to the roof of the locomotive cab using a fastener, epoxy or the like.
FIGS. 3-5 illustrate another prior art system for mounting a plurality of antennas 202(A-F) to a locomotive cab roof 206. In this system, a metal base plate 214 is affixed to the locomotive cab roof 206 using a plurality of fasteners 210 and RTV to prevent water ingress. The metal base plate 214 accommodates a raised antenna mount 204 and a cover (or radome) 208 for the mount. In this arrangement, the raised antenna mount 204 and the cover 208 are affixed to the metal base plate 214. The raised antenna mount 204 accommodates a plurality of antennas 202A-F. The wiring 212, as shown in FIG. 5, for the antennas 202A-F is fed through an aperture defined in the metal base plate 208, through an aperture defined in the roof 206 of the locomotive cab 218, and terminates in the locomotive cab 218 generally at the devices associated therewith, as shown in FIG. 5. The wiring 216 used with the antenna mount 204 is a crimp style connection, which includes fluctuations in the resistance of the connector.
Like the prior art system of FIG. 2, the prior art system of FIGS. 3-5 has several shortcomings. For example, each antenna 202 cannot be easily arranged or rearranged in order to overcome communication or RF interference with other antennas. Moreover, the management of the wiring 212 from each antenna to their respective devices is cumbersome. Additionally, because the roof 206 of the locomotive is susceptible to harsh environmental conditions, the prior art system and the locomotive cab become susceptible to water ingress due to deterioration of the fasteners 210 and RTV of the metal base plate 214, raised antenna mount 204, and cover 208. The replacement of an antenna 202 in this prior art system also proves to be difficult and labor intensive. Replacement of the antenna 202 first requires the removal of the deteriorated fasteners 210 at the cover 208 and the entire antenna mount 204. Also, all of the wiring 212 extending from the previous antenna to the device associated therewith must be removed. Then, new wiring 212 is fed into the locomotive cab 218 via the wire connection arrangement 216, where it is connected to a device for utilization of that particular antenna 202. The antenna 202 is affixed to the antenna mount 204, the entire antenna mount is reaffixed to the metal base plate 214, and the cover 208 is reaffixed to the metal base plate 214.
Accordingly, it is an object of the present invention to provide an antenna mounting apparatus that minimizes water ingress into the cab of a locomotive. It is also an object of the present invention to provide an antenna mounting apparatus that provides easy arrangement and/or rearrangement of the antenna in order to overcome RF interference with other antenna. It is an object of the present invention to provide an apparatus for managing the wiring near each antenna. Finally, it is an object of the present invention to provide an antenna mounting apparatus which is modular and provides for easy maintenance and replacement of a single antenna in a multiple antenna system.